1. Field of the Invention
This invention relates generally to electronic circuits used to expand the amplitude dynamic range of an instrumentation tape recorder and more particularly to such circuits employing piece-wise linear approximations.
2. Description of the Prior Art
The conventional method of expanding the amplitude dynamic range of instrumentation tape recorders includes the use of a logarithmic gain curve for recording. This has the effect of boosting low level signals above recorder noise and suppressing high level signals so that greater input signal swing can be achieved before maximum deviation of a recorder voltage-controlled oscillator is reached. At playback, an anti-log gain curve is used so that the net result will be a linear output signal. However, the gain curves from such logarithmic systems are extremely difficult to accurately calibrate.